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The New Hampshire dominoes

From NBC's Doug AdamsNew Hampshire governor John Lynch is holding a news conference at 4:30 p.m. today to announce a successor to Sen. Judd Gregg -- if Gregg is confirmed as Commerce Secretary.

The pick is expected to be a Republican -- part of a deal worked out by Gregg, a Republican, and Lynch, a Democrat. The appointee would reportedly agree to be a "caretaker" for two years, and not run in the 2010 election.

The expected choice is Bonnie Newman, a 63-year-old Republican with a long biography of high profile political and educational appointments. She has served in two Republican administrations (Reagan and George H.W. Bush) and has close ties to Sen. Gregg, having been his chief of staff in the House in the 1980s. She was once president of the University of New Hampshire and executive dean of Harvard's Kennedy School of Government.

Though the deal to appoint a caretaker Republican has raised anger from both sides in New Hampshire, Lynch does have a history of reaching across party lines -- having appointed Republicans to several top positions in his administration. Newman and Lynch also have a close working relationship -- she was one of the first Republicans to endorse him in 2004 when he first ran for governor.

That being said, it is pretty rare for a governor to reach across the aisle on a Senate pick. The last time a governor freely chose a member of the other party to replace an outgoing senator was in 1960, when Republican Gov. Mark Hatfield of Oregon chose a Democrat to replace a Democratic senator who died.

As for the Republicans in 2010 -- if Gregg's appointment is indeed a caretaker -- the list begins with former Sen. John Sununu Jr. At 45, he was the youngest member of the U.S. Senate, and he lost a bitter election to Jeanne Shaheen last fall.

Other names that mentioned by New Hampshire politicos are former Rep. Charlie Bass, who lost his re-election race in 2006 and has already expressed interest in the seat; and former Manchester mayor Frank Guinta.

For the Democrats, Rep. Paul Hodes is wasting no time in declaring his intent to run for the seat in 2010.

The New Hampshire Union Leader is reporting that Hodes will announce his candidacy this week. Another House member, Carol Shea Porter, is not ruling out a run, which would set up a messy primary for the Democrats.

The other question is whether Lynch himself might run in 2010, which is when his gubernatorial term ends. He is easily the most popular Democrat in the state.